1. Field of the Invention
The present invention relates to a high-density optical disc such as BD-RE (Blu-ray Disc Rewritable) or BD-ROM, and a recording/reproducing method thereof.
2. Description of the Related Art
Recently, high-density optical discs have been developed, for example, DVD (Digital Versatile Disc), which can store a large quantity of high-quality video and audio data. Currently, such high-density optical discs are widely commercially available.
On a DVD, main A/V data is recorded in the unit of sectors each having a size of 2,084 bytes, as shown in FIG. 1. In each sector of 2,048 bytes, additional information of 16 bytes is recorded which may include ID (Identification Data), IED (ID Error Detection Code), CPR_MAI (Copyright Management Information), and EDC (Error Detection Code).
The sector ID information, which is included in the additional information, consists of 4 bytes including 1-byte sector information and 3-byte sector number information, as shown in FIG. 2.
The 1-byte sector information includes sector format type information, tracking method information, disc reflectivity information, reserved information, data type information, and layer number information, each of which has a size of 1 bit. The sector information also includes area type information of 2 bits.
For example, where the sector formation type information corresponds to ‘0b’, it represents that the main A/V data recorded on the associated sector can be reproduced or recorded by a CLV (Constant Linear Velocity) type. On the other hand, where the sector formation type information corresponds to ‘1b’, it represents that the main A/V data recorded on the associated sector can be reproduced or recorded by different types for different zones, respectively.
Also, where the tracking method information corresponds to ‘0b’, it represents a pit-based tracking operation. On the other hand, where the tracking method information corresponds to ‘1b’, it represents a groove-based tracking operation. Where the disc reflectivity information corresponds to ‘0b’, it represents a reflectivity of more than 40%. On the other hand, where the reflectivity information corresponds to ‘1b’, it represents a reflectivity of not more than 40%.
Meanwhile, where the area type information corresponds to ‘00b’, it represents that the current position corresponds to a data area. Also, where the area type information corresponds to ‘01b’, it represents that the current position corresponds to a lead-in area. The area type information corresponding to ‘01b’ represents a lead-out area, whereas the area type information corresponding to ‘11b’ represents a middle area on a dual layer optical disc. Where the data type information corresponds to ‘0b’, it represents that the main A/V data of the associated sector is read-only data. On the other hand, where the data type information corresponds to ‘1b’, it represents that the main A/V data of the associated sector is data other than read-only data.
Also, where the layer number information corresponds to ‘0b’, it represents that the current disc has a single layer or that the current layer is a first layer Layer 0 in a dual layer optical disc. On the other hand, where the layer number information corresponds to ‘1b’, it represents that the current layer is a second layer Layer 1 in the dual layer optical disc.
Accordingly, once such a DVD is loaded in an optical disc apparatus, the optical disc apparatus reads sector format type information, tracking method information, disc reflectivity information, data type information, layer number information, and area type information recorded on the DVD as sector information, in order to normally carry out a data recording or reproducing operation corresponding to the read information.
For example, servo control for data recording or reproduction should be determined in accordance with whether the sector formation type information represents a CLV type or a different type having different linear velocities for respective zones. Also, the gain of a read signal should be determined in accordance with the disc reflectivity information. Focus servo control also has to be determined in accordance with the layer information. Thus, the recording or reproducing condition should be determined in accordance with the additional information.
Meanwhile, standardization of new high-density optical discs such as BD-RE and BD-ROM has recently been conducted by associated companies. However, the data format of such BDs is essentially different from that of DVDs. Furthermore, there is no method for effectively and appropriately recording diverse information corresponding to sector information, as recorded on a DVD, on the above mentioned high-density optical disc. Accordingly, such a method is strongly demanded.